From afaa53040bd01ca86762e7d7b1a5a65810767921 Mon Sep 17 00:00:00 2001 From: Robert Ellison Date: Fri, 3 Oct 2008 18:00:43 -0600 Subject: CELL: changes to generate SPU code for stenciling This set of code changes are for stencil code generation support. Both one-sided and two-sided stenciling are supported. In addition to the raw code generation changes, these changes had to be made elsewhere in the system: - Added new "register set" feature to the SPE assembly generation. A "register set" is a way to allocate multiple registers and free them all at the same time, delegating register allocation management to the spe_function unit. It's quite useful in complex register allocation schemes (like stenciling). - Added and improved SPE macro calculations. These are operations between registers and unsigned integer immediates. In many cases, the calculation can be performed with a single instruction; the macros will generate the single instruction if possible, or generate a register load and register-to-register operation if not. These macro functions are: spe_load_uint() (which has new ways to load a value in a single instruction), spe_and_uint(), spe_xor_uint(), spe_compare_equal_uint(), and spe_compare_greater_uint(). - Added facing to fragment generation. While rendering, the rasterizer needs to be able to determine front- and back-facing fragments, in order to correctly apply two-sided stencil. That requires these changes: - Added front_winding field to the cell_command_render block, so that the state tracker could communicate to the rasterizer what it considered to be the front-facing direction. - Added fragment facing as an input to the fragment function. - Calculated facing is passed during emit_quad(). --- src/gallium/drivers/cell/ppu/cell_gen_fragment.c | 881 ++++++++++++++++++++--- 1 file changed, 785 insertions(+), 96 deletions(-) (limited to 'src/gallium/drivers/cell/ppu/cell_gen_fragment.c') diff --git a/src/gallium/drivers/cell/ppu/cell_gen_fragment.c b/src/gallium/drivers/cell/ppu/cell_gen_fragment.c index 653afc235d..f920ae13b4 100644 --- a/src/gallium/drivers/cell/ppu/cell_gen_fragment.c +++ b/src/gallium/drivers/cell/ppu/cell_gen_fragment.c @@ -54,10 +54,12 @@ * \param ifragZ_reg register containing integer fragment Z values (in) * \param ifbZ_reg register containing integer frame buffer Z values (in/out) * \param zmask_reg register containing result of Z test/comparison (out) + * + * Returns true if the Z-buffer needs to be updated. */ -static void -gen_depth_test(const struct pipe_depth_stencil_alpha_state *dsa, - struct spe_function *f, +static boolean +gen_depth_test(struct spe_function *f, + const struct pipe_depth_stencil_alpha_state *dsa, int mask_reg, int ifragZ_reg, int ifbZ_reg, int zmask_reg) { /* NOTE: we use clgt below, not cgt, because we want to compare _unsigned_ @@ -132,7 +134,10 @@ gen_depth_test(const struct pipe_depth_stencil_alpha_state *dsa, * framebufferZ = (ztest_passed ? fragmentZ : framebufferZ; */ spe_selb(f, ifbZ_reg, ifbZ_reg, ifragZ_reg, mask_reg); + return true; } + + return false; } @@ -238,22 +243,34 @@ gen_alpha_test(const struct pipe_depth_stencil_alpha_state *dsa, * it and have to allocate and load it again unnecessarily. */ static inline void -setup_const_register(struct spe_function *f, boolean *is_already_set, unsigned int *r, float value) +setup_optional_register(struct spe_function *f, boolean *is_already_set, unsigned int *r) { if (*is_already_set) return; *r = spe_allocate_available_register(f); - spe_load_float(f, *r, value); - *is_already_set = true; } static inline void -release_const_register(struct spe_function *f, boolean *is_already_set, unsigned int r) +release_optional_register(struct spe_function *f, boolean *is_already_set, unsigned int r) { if (!*is_already_set) return; spe_release_register(f, r); *is_already_set = false; } +static inline void +setup_const_register(struct spe_function *f, boolean *is_already_set, unsigned int *r, float value) +{ + if (*is_already_set) return; + setup_optional_register(f, is_already_set, r); + spe_load_float(f, *r, value); +} + +static inline void +release_const_register(struct spe_function *f, boolean *is_already_set, unsigned int r) +{ + release_optional_register(f, is_already_set, r); +} + /** * Generate SPE code to implement the given blend mode for a quad of pixels. * \param f SPE function to append instruction onto. @@ -1117,6 +1134,633 @@ gen_colormask(struct spe_function *f, spe_release_register(f, colormask_reg); } +/* This function is annoyingly similar to gen_depth_test(), above, except + * that instead of comparing two varying values (i.e. fragment and buffer), + * we're comparing a varying value with a static value. As such, we have + * access to the Compare Immediate instructions where we don't in + * gen_depth_test(), which is what makes us very different. + * + * The return value in the stencil_pass_reg is a bitmask of valid + * fragments that also passed the stencil test. The bitmask of valid + * fragments that failed would be found in (mask_reg & ~stencil_pass_reg). + */ +static void +gen_stencil_test(struct spe_function *f, const struct pipe_stencil_state *state, + unsigned int mask_reg, unsigned int fbS_reg, + unsigned int stencil_pass_reg) +{ + /* Generate code that puts the set of passing fragments into the stencil_pass_reg + * register, taking into account whether each fragment was active to begin with. + */ + switch (state->func) { + case PIPE_FUNC_EQUAL: + /* stencil_pass = mask & (s == reference) */ + spe_compare_equal_uint(f, stencil_pass_reg, fbS_reg, state->ref_value); + spe_and(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + /* stencil_fail = mask & ~stencil_pass */ + break; + + case PIPE_FUNC_NOTEQUAL: + /* stencil_pass = mask & ~(s == reference) */ + spe_compare_equal_uint(f, stencil_pass_reg, fbS_reg, state->ref_value); + spe_andc(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + break; + + case PIPE_FUNC_GREATER: + /* stencil_pass = mask & (s > reference) */ + spe_compare_greater_uint(f, stencil_pass_reg, fbS_reg, state->ref_value); + spe_and(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + break; + + case PIPE_FUNC_LESS: { + /* stencil_pass = mask & (reference > s) */ + /* There's no convenient Compare Less Than Immediate instruction, so + * we'll have to do this one the harder way, by loading a register and + * comparing directly. Compare Logical Greater Than Word (clgt) + * treats its operands as unsigned - no sign extension. + */ + unsigned int tmp_reg = spe_allocate_available_register(f); + spe_load_uint(f, tmp_reg, state->ref_value); + spe_clgt(f, stencil_pass_reg, tmp_reg, fbS_reg); + spe_and(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + spe_release_register(f, tmp_reg); + break; + } + + case PIPE_FUNC_LEQUAL: + /* stencil_pass = mask & (s <= reference) = mask & ~(s > reference) */ + spe_compare_greater_uint(f, stencil_pass_reg, fbS_reg, state->ref_value); + spe_andc(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + break; + + case PIPE_FUNC_GEQUAL: { + /* stencil_pass = mask & (s >= reference) = mask & ~(reference > s) */ + /* As above, we have to do this by loading a register */ + unsigned int tmp_reg = spe_allocate_available_register(f); + spe_load_uint(f, tmp_reg, state->ref_value); + spe_clgt(f, stencil_pass_reg, tmp_reg, fbS_reg); + spe_andc(f, stencil_pass_reg, mask_reg, stencil_pass_reg); + spe_release_register(f, tmp_reg); + break; + } + + case PIPE_FUNC_NEVER: + /* stencil_pass = mask & 0 = 0 */ + spe_load_uint(f, stencil_pass_reg, 0); + spe_move(f, stencil_pass_reg, mask_reg); /* zmask = mask */ + break; + + case PIPE_FUNC_ALWAYS: + /* stencil_pass = mask & 1 = mask */ + spe_move(f, stencil_pass_reg, mask_reg); + break; + } + + /* The fragments that passed the stencil test are now in stencil_pass_reg. + * The fragments that failed would be (mask_reg & ~stencil_pass_reg). + */ +} + +/* This function generates code that calculates a set of new stencil values + * given the earlier values and the operation to apply. It does not + * apply any tests. It is intended to be called up to 3 times + * (for the stencil fail operation, for the stencil pass-z fail operation, + * and for the stencil pass-z pass operation) to collect up to three + * possible sets of values, and for the caller to combine them based + * on the result of the tests. + * + * stencil_max_value should be (2^n - 1) where n is the number of bits + * in the stencil buffer - in other words, it should be usable as a mask. + */ +static void +gen_stencil_values(struct spe_function *f, unsigned int stencil_op, + unsigned int stencil_ref_value, unsigned int stencil_max_value, + unsigned int fbS_reg, unsigned int newS_reg) +{ + /* The code below assumes that newS_reg and fbS_reg are not the same + * register; if they can be, the calculations below will have to use + * an additional temporary register. For now, mark the assumption + * with an assertion that will fail if they are the same. + */ + ASSERT(fbS_reg != newS_reg); + + /* The code also assumes the the stencil_max_value is of the form + * 2^n-1 and can therefore be used as a mask for the valid bits in + * addition to a maximum. Make sure this is the case as well. + * The clever math below exploits the fact that incrementing a + * binary number serves to flip all the bits of a number starting at + * the LSB and continuing to (and including) the first zero bit + * found. That means that a number and its increment will always + * have at least one bit in common (the high order bit, if nothing + * else) *unless* the number is zero, *or* the number is of a form + * consisting of some number of 1s in the low-order bits followed + * by nothing but 0s in the high-order bits. The latter case + * implies it's of the form 2^n-1. + */ + ASSERT(stencil_max_value > 0 && ((stencil_max_value + 1) & stencil_max_value) == 0); + + switch(stencil_op) { + case PIPE_STENCIL_OP_KEEP: + /* newS = S */ + spe_move(f, newS_reg, fbS_reg); + break; + + case PIPE_STENCIL_OP_ZERO: + /* newS = 0 */ + spe_zero(f, newS_reg); + break; + + case PIPE_STENCIL_OP_REPLACE: + /* newS = stencil reference value */ + spe_load_uint(f, newS_reg, stencil_ref_value); + break; + + case PIPE_STENCIL_OP_INCR: { + /* newS = (s == max ? max : s + 1) */ + unsigned int equals_reg = spe_allocate_available_register(f); + + spe_compare_equal_uint(f, equals_reg, fbS_reg, stencil_max_value); + /* Add Word Immediate computes rT = rA + 10-bit signed immediate */ + spe_ai(f, newS_reg, fbS_reg, 1); + /* Select from the current value or the new value based on the equality test */ + spe_selb(f, newS_reg, fbS_reg, newS_reg, equals_reg); + + spe_release_register(f, equals_reg); + break; + } + case PIPE_STENCIL_OP_DECR: { + /* newS = (s == 0 ? 0 : s - 1) */ + unsigned int equals_reg = spe_allocate_available_register(f); + + spe_compare_equal_uint(f, equals_reg, fbS_reg, 0); + /* Add Word Immediate with a (-1) value works */ + spe_ai(f, newS_reg, fbS_reg, -1); + /* Select from the current value or the new value based on the equality test */ + spe_selb(f, newS_reg, fbS_reg, newS_reg, equals_reg); + + spe_release_register(f, equals_reg); + break; + } + case PIPE_STENCIL_OP_INCR_WRAP: + /* newS = (s == max ? 0 : s + 1), but since max is 2^n-1, we can + * do a normal add and mask off the correct bits + */ + spe_ai(f, newS_reg, fbS_reg, 1); + spe_and_uint(f, newS_reg, newS_reg, stencil_max_value); + break; + + case PIPE_STENCIL_OP_DECR_WRAP: + /* newS = (s == 0 ? max : s - 1), but we'll pull the same mask trick as above */ + spe_ai(f, newS_reg, fbS_reg, -1); + spe_and_uint(f, newS_reg, newS_reg, stencil_max_value); + break; + + case PIPE_STENCIL_OP_INVERT: + /* newS = ~s. We take advantage of the mask/max value to invert only + * the valid bits for the field so we don't have to do an extra "and". + */ + spe_xor_uint(f, newS_reg, fbS_reg, stencil_max_value); + break; + + default: + ASSERT(0); + } +} + + +/* This function generates code to get all the necessary possible + * stencil values. For each of the output registers (fail_reg, + * zfail_reg, and zpass_reg), it either allocates a new register + * and calculates a new set of values based on the stencil operation, + * or it reuses a register allocation and calculation done for an + * earlier (matching) operation, or it reuses the fbS_reg register + * (if the stencil operation is KEEP, which doesn't change the + * stencil buffer). + * + * Since this function allocates a variable number of registers, + * to avoid incurring complex logic to free them, they should + * be allocated after a spe_allocate_register_set() call + * and released by the corresponding spe_release_register_set() call. + */ +static void +gen_get_stencil_values(struct spe_function *f, const struct pipe_depth_stencil_alpha_state *dsa, + unsigned int fbS_reg, + unsigned int *fail_reg, unsigned int *zfail_reg, + unsigned int *zpass_reg, unsigned int *back_fail_reg, + unsigned int *back_zfail_reg, unsigned int *back_zpass_reg) +{ + unsigned zfail_op, back_zfail_op; + + /* Stenciling had better be enabled here */ + ASSERT(dsa->stencil[0].enabled); + + /* If the depth test is not enabled, it is treated as though it always + * passes. In particular, that means that the "zfail_op" (and the backfacing + * counterpart, if active) are not considered - a failing stencil test will + * trigger the "fail_op", and a passing stencil test will trigger the + * "zpass_op". + * + * By overriding the operations in this case to be PIPE_STENCIL_OP_KEEP, + * we keep them from being calculated. + */ + if (dsa->depth.enabled) { + zfail_op = dsa->stencil[0].zfail_op; + back_zfail_op = dsa->stencil[1].zfail_op; + } + else { + zfail_op = PIPE_STENCIL_OP_KEEP; + back_zfail_op = PIPE_STENCIL_OP_KEEP; + } + + /* One-sided or front-facing stencil */ + if (dsa->stencil[0].fail_op == PIPE_STENCIL_OP_KEEP) { + *fail_reg = fbS_reg; + } + else { + *fail_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[0].fail_op, dsa->stencil[0].ref_value, + 0xff, fbS_reg, *fail_reg); + } + + if (zfail_op == PIPE_STENCIL_OP_KEEP) { + *zfail_reg = fbS_reg; + } + else if (zfail_op == dsa->stencil[0].fail_op) { + *zfail_reg = *fail_reg; + } + else { + *zfail_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[0].zfail_op, dsa->stencil[0].ref_value, + 0xff, fbS_reg, *zfail_reg); + } + + if (dsa->stencil[0].zpass_op == PIPE_STENCIL_OP_KEEP) { + *zpass_reg = fbS_reg; + } + else if (dsa->stencil[0].zpass_op == dsa->stencil[0].fail_op) { + *zpass_reg = *fail_reg; + } + else if (dsa->stencil[0].zpass_op == zfail_op) { + *zpass_reg = *zfail_reg; + } + else { + *zpass_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[0].zpass_op, dsa->stencil[0].ref_value, + 0xff, fbS_reg, *zpass_reg); + } + + /* If two-sided stencil is enabled, we have more work to do. */ + if (!dsa->stencil[1].enabled) { + /* This just flags that the registers need not be deallocated later */ + *back_fail_reg = fbS_reg; + *back_zfail_reg = fbS_reg; + *back_zpass_reg = fbS_reg; + } + else { + /* Same calculations as above, but for the back stencil */ + if (dsa->stencil[1].fail_op == PIPE_STENCIL_OP_KEEP) { + *back_fail_reg = fbS_reg; + } + else if (dsa->stencil[1].fail_op == dsa->stencil[0].fail_op) { + *back_fail_reg = *fail_reg; + } + else if (dsa->stencil[1].fail_op == zfail_op) { + *back_fail_reg = *zfail_reg; + } + else if (dsa->stencil[1].fail_op == dsa->stencil[0].zpass_op) { + *back_fail_reg = *zpass_reg; + } + else { + *back_fail_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[1].fail_op, dsa->stencil[1].ref_value, + 0xff, fbS_reg, *back_fail_reg); + } + + if (back_zfail_op == PIPE_STENCIL_OP_KEEP) { + *back_zfail_reg = fbS_reg; + } + else if (back_zfail_op == dsa->stencil[0].fail_op) { + *back_zfail_reg = *fail_reg; + } + else if (back_zfail_op == zfail_op) { + *back_zfail_reg = *zfail_reg; + } + else if (back_zfail_op == dsa->stencil[0].zpass_op) { + *back_zfail_reg = *zpass_reg; + } + else if (back_zfail_op == dsa->stencil[1].fail_op) { + *back_zfail_reg = *back_fail_reg; + } + else { + *back_zfail_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[1].zfail_op, dsa->stencil[1].ref_value, + 0xff, fbS_reg, *back_zfail_reg); + } + + if (dsa->stencil[1].zpass_op == PIPE_STENCIL_OP_KEEP) { + *back_zpass_reg = fbS_reg; + } + else if (dsa->stencil[1].zpass_op == dsa->stencil[0].fail_op) { + *back_zpass_reg = *fail_reg; + } + else if (dsa->stencil[1].zpass_op == zfail_op) { + *back_zpass_reg = *zfail_reg; + } + else if (dsa->stencil[1].zpass_op == dsa->stencil[0].zpass_op) { + *back_zpass_reg = *zpass_reg; + } + else if (dsa->stencil[1].zpass_op == dsa->stencil[1].fail_op) { + *back_zpass_reg = *back_fail_reg; + } + else if (dsa->stencil[1].zpass_op == back_zfail_op) { + *back_zpass_reg = *back_zfail_reg; + } + else { + *back_zfail_reg = spe_allocate_available_register(f); + gen_stencil_values(f, dsa->stencil[1].zpass_op, dsa->stencil[1].ref_value, + 0xff, fbS_reg, *back_zpass_reg); + } + } /* End of calculations for back-facing stencil */ +} + +static boolean +gen_stencil_depth_test(struct spe_function *f, + const struct pipe_depth_stencil_alpha_state *dsa, + const int const facing_reg, + const int mask_reg, const int fragZ_reg, + const int fbZ_reg, const int fbS_reg) +{ + /* True if we've generated code that could require writeback to the + * depth and/or stencil buffers + */ + boolean modified_buffers = false; + + boolean need_to_calculate_stencil_values; + boolean need_to_writemask_stencil_values; + + /* Registers. We may or may not actually allocate these, depending + * on whether the state values indicate that we need them. + */ + unsigned int stencil_pass_reg, stencil_fail_reg; + unsigned int stencil_fail_values, stencil_pass_depth_fail_values, stencil_pass_depth_pass_values; + unsigned int stencil_writemask_reg; + unsigned int zmask_reg; + unsigned int newS_reg; + + /* Stenciling is quite complex: up to six different configurable stencil + * operations/calculations can be required (three each for front-facing + * and back-facing fragments). Many of those operations will likely + * be identical, so there's good reason to try to avoid calculating + * the same values more than once (which unfortunately makes the code less + * straightforward). + * + * To make register management easier, we start a new + * register set; we can release all the registers in the set at + * once, and avoid having to keep track of exactly which registers + * we allocate. We can still allocate and free registers as + * desired (if we know we no longer need a register), but we don't + * have to spend the complexity to track the more difficult variant + * register usage scenarios. + */ + spe_allocate_register_set(f); + + /* Calculate the writemask. If the writemask is trivial (either + * all 0s, meaning that we don't need to calculate any stencil values + * because they're not going to change the stencil anyway, or all 1s, + * meaning that we have to calculate the stencil values but do not + * need to mask them), we can avoid generating code. Don't forget + * that we need to consider backfacing stencil, if enabled. + */ + if (dsa->stencil[0].write_mask == 0x0 && (!dsa->stencil[1].enabled || dsa->stencil[1].write_mask == 0x00)) { + /* Trivial: don't need to calculate stencil values, and don't need to + * write them back to the framebuffer. + */ + need_to_calculate_stencil_values = false; + need_to_writemask_stencil_values = false; + } + else if (dsa->stencil[0].write_mask == 0xff && (!dsa->stencil[1].enabled || dsa->stencil[1].write_mask == 0x00)) { + /* Still trivial, but a little less so. We need to write the stencil + * values, but we don't need to mask them. + */ + need_to_calculate_stencil_values = true; + need_to_writemask_stencil_values = false; + } + else { + /* The general case: calculate, mask, and write */ + need_to_calculate_stencil_values = true; + need_to_writemask_stencil_values = true; + + /* While we're here, generate code that calculates what the + * writemask should be. If backface stenciling is enabled, + * and the backface writemask is not the same as the frontface + * writemask, we'll have to generate code that merges the + * two masks into a single effective mask based on fragment facing. + */ + stencil_writemask_reg = spe_allocate_available_register(f); + spe_load_uint(f, stencil_writemask_reg, dsa->stencil[0].write_mask); + if (dsa->stencil[1].enabled && dsa->stencil[0].write_mask != dsa->stencil[1].write_mask) { + unsigned int back_write_mask_reg = spe_allocate_available_register(f); + spe_load_uint(f, back_write_mask_reg, dsa->stencil[1].write_mask); + spe_selb(f, stencil_writemask_reg, stencil_writemask_reg, back_write_mask_reg, facing_reg); + spe_release_register(f, back_write_mask_reg); + } + } + + /* At least one-sided stenciling must be on. Generate code that + * runs the stencil test on the basic/front-facing stencil, leaving + * the mask of passing stencil bits in stencil_pass_reg. This mask will + * be used both to mask the set of active pixels, and also to + * determine how the stencil buffer changes. + * + * This test will *not* change the value in mask_reg (because we don't + * yet know whether to apply the two-sided stencil or one-sided stencil). + */ + stencil_pass_reg = spe_allocate_available_register(f); + gen_stencil_test(f, &dsa->stencil[0], mask_reg, fbS_reg, stencil_pass_reg); + + /* If two-sided stenciling is on, generate code to run the stencil + * test on the backfacing stencil as well, and combine the two results + * into the one correct result based on facing. + */ + if (dsa->stencil[1].enabled) { + unsigned int temp_reg = spe_allocate_available_register(f); + gen_stencil_test(f, &dsa->stencil[1], mask_reg, fbS_reg, temp_reg); + spe_selb(f, stencil_pass_reg, stencil_pass_reg, temp_reg, facing_reg); + spe_release_register(f, temp_reg); + } + + /* Generate code that, given the mask of valid fragments and the + * mask of valid fragments that passed the stencil test, computes + * the mask of valid fragments that failed the stencil test. We + * have to do this before we run a depth test (because the + * depth test should not be performed on fragments that failed the + * stencil test, and because the depth test will update the + * mask of valid fragments based on the results of the depth test). + */ + stencil_fail_reg = spe_allocate_available_register(f); + spe_andc(f, stencil_fail_reg, mask_reg, stencil_pass_reg); + /* Now remove the stenciled-out pixels from the valid fragment mask, + * so we can later use the valid fragment mask in the depth test. + */ + spe_and(f, mask_reg, mask_reg, stencil_pass_reg); + + /* We may not need to calculate stencil values, if the writemask is off */ + if (need_to_calculate_stencil_values) { + unsigned int back_stencil_fail_values, back_stencil_pass_depth_fail_values, back_stencil_pass_depth_pass_values; + unsigned int front_stencil_fail_values, front_stencil_pass_depth_fail_values, front_stencil_pass_depth_pass_values; + + /* Generate code that calculates exactly which stencil values we need, + * without calculating the same value twice (say, if two different + * stencil ops have the same value). This code will work for one-sided + * and two-sided stenciling (so that we take into account that operations + * may match between front and back stencils), and will also take into + * account whether the depth test is enabled (if the depth test is off, + * we don't need any of the zfail results, because the depth test always + * is considered to pass if it is disabled). Any register value that + * does not need to be calculated will come back with the same value + * that's in fbS_reg. + * + * This function will allocate a variant number of registers that + * will be released as part of the register set. + */ + gen_get_stencil_values(f, dsa, fbS_reg, + &front_stencil_fail_values, &front_stencil_pass_depth_fail_values, + &front_stencil_pass_depth_pass_values, &back_stencil_fail_values, + &back_stencil_pass_depth_fail_values, &back_stencil_pass_depth_pass_values); + + /* Tricky, tricky, tricky - the things we do to create optimal + * code... + * + * The various stencil values registers may overlap with each other + * and with fbS_reg arbitrarily (as any particular operation is + * only calculated once and stored in one register, no matter + * how many times it is used). So we can't change the values + * within those registers directly - if we change a value in a + * register that's being referenced by two different calculations, + * we've just unwittingly changed the second value as well... + * + * Avoid this by allocating new registers to hold the results + * (there may be 2, if the depth test is off, or 3, if it is on). + * These will be released as part of the register set. + */ + if (!dsa->stencil[1].enabled) { + /* The easy case: if two-sided stenciling is *not* enabled, we + * just use the front-sided values. + */ + stencil_fail_values = front_stencil_fail_values; + stencil_pass_depth_fail_values = front_stencil_pass_depth_fail_values; + stencil_pass_depth_pass_values = front_stencil_pass_depth_pass_values; + } + else { /* two-sided stencil enabled */ + /* Allocate new registers for the needed merged values */ + stencil_fail_values = spe_allocate_available_register(f); + spe_selb(f, stencil_fail_values, front_stencil_fail_values, back_stencil_fail_values, facing_reg); + if (dsa->depth.enabled) { + stencil_pass_depth_fail_values = spe_allocate_available_register(f); + spe_selb(f, stencil_pass_depth_fail_values, front_stencil_pass_depth_fail_values, back_stencil_pass_depth_fail_values, facing_reg); + } + else { + stencil_pass_depth_fail_values = fbS_reg; + } + stencil_pass_depth_pass_values = spe_allocate_available_register(f); + spe_selb(f, stencil_pass_depth_pass_values, front_stencil_pass_depth_pass_values, back_stencil_pass_depth_pass_values, facing_reg); + } + } + + /* We now have all the stencil values we need. We also need + * the results of the depth test to figure out which + * stencil values will become the new stencil values. (Even if + * we aren't actually calculating stencil values, we need to apply + * the depth test if it's enabled.) + * + * The code generated by gen_depth_test() returns the results of the + * test in the given register, but also alters the mask_reg based + * on the results of the test. + */ + if (dsa->depth.enabled) { + zmask_reg = spe_allocate_available_register(f); + modified_buffers |= gen_depth_test(f, dsa, mask_reg, fragZ_reg, fbZ_reg, zmask_reg); + } + + if (need_to_calculate_stencil_values) { + /* If we need to writemask the stencil values before going into + * the stencil buffer, we'll have to use a new register to + * hold the new values. If not, we can just keep using the + * current register. + */ + if (need_to_writemask_stencil_values) { + newS_reg = spe_allocate_available_register(f); + spe_move(f, newS_reg, fbS_reg); + modified_buffers = true; + } + else { + newS_reg = fbS_reg; + } + + /* Merge in the selected stencil fail values */ + if (stencil_fail_values != fbS_reg) { + spe_selb(f, newS_reg, newS_reg, stencil_fail_values, stencil_fail_reg); + } + + /* Same for the stencil pass/depth fail values. If this calculation + * is not needed (say, if depth test is off), then the + * stencil_pass_depth_fail_values register will be equal to fbS_reg + * and we'll skip the calculation. + */ + if (stencil_pass_depth_fail_values != fbS_reg) { + /* We don't actually have a stencil pass/depth fail mask yet. + * Calculate it here from the stencil passing mask and the + * depth passing mask. Note that zmask_reg *must* have been + * set above if we're here. + */ + unsigned int stencil_pass_depth_fail_mask = spe_allocate_available_register(f); + spe_andc(f, stencil_pass_depth_fail_mask, stencil_pass_reg, zmask_reg); + + spe_selb(f, newS_reg, newS_reg, stencil_pass_depth_fail_values, stencil_pass_depth_fail_mask); + + spe_release_register(f, stencil_pass_depth_fail_mask); + } + + /* Same for the stencil pass/depth pass mask */ + if (stencil_pass_depth_pass_values != fbS_reg) { + unsigned int stencil_pass_depth_pass_mask = spe_allocate_available_register(f); + spe_and(f, stencil_pass_depth_pass_mask, stencil_pass_reg, zmask_reg); + + spe_selb(f, newS_reg, newS_reg, stencil_pass_depth_pass_values, stencil_pass_depth_pass_mask); + spe_release_register(f, stencil_pass_depth_pass_mask); + } + + /* Almost done. If we need to writemask, do it now, leaving the + * results in the fbS_reg register passed in. If we don't need + * to writemask, then the results are *already* in the fbS_reg, + * so there's nothing more to do. + */ + + if (need_to_writemask_stencil_values) { + /* The Select Bytes command makes a fine writemask. Where + * the mask is 0, the first (original) values are retained, + * effectively masking out changes. Where the mask is 1, the + * second (new) values are retained, incorporating changes. + */ + spe_selb(f, fbS_reg, fbS_reg, newS_reg, stencil_writemask_reg); + } + } /* done calculating stencil values */ + + /* The stencil and/or depth values have been applied, and the + * mask_reg, fbS_reg, and fbZ_reg values have been updated. + * We're all done, except that we've allocated a fair number + * of registers that we didn't bother tracking. Release all + * those registers as part of the register set, and go home. + */ + spe_release_register_set(f); + + /* Return true if we could have modified the stencil and/or + * depth buffers. + */ + return modified_buffers; +} + + /** * Generate SPE code to implement the fragment operations (alpha test, * depth test, stencil test, blending, colormask, and final @@ -1156,6 +1800,7 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) const int fragB_reg = 10; /* vector float */ const int fragA_reg = 11; /* vector float */ const int mask_reg = 12; /* vector uint */ + const int facing_reg = 13; /* uint */ /* offset of quad from start of tile * XXX assuming 4-byte pixels for color AND Z/stencil!!!! @@ -1183,6 +1828,7 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) spe_allocate_register(f, fragB_reg); spe_allocate_register(f, fragA_reg); spe_allocate_register(f, mask_reg); + spe_allocate_register(f, facing_reg); quad_offset_reg = spe_allocate_available_register(f); fbRGBA_reg = spe_allocate_available_register(f); @@ -1195,6 +1841,7 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) ASSERT(TILE_SIZE == 32); + spe_comment(f, 0, "Computing tile location in memory"); spe_rotmi(f, y2_reg, y_reg, -1); /* y2 = y / 2 */ spe_rotmi(f, x2_reg, x_reg, -1); /* x2 = x / 2 */ spe_shli(f, y2_reg, y2_reg, 4); /* y2 *= 16 */ @@ -1205,124 +1852,164 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) spe_release_register(f, y2_reg); } - if (dsa->alpha.enabled) { gen_alpha_test(dsa, f, mask_reg, fragA_reg); } + /* If we need the stencil buffers (because one- or two-sided stencil is + * enabled) or the depth buffer (because the depth test is enabled), + * go grab them. Note that if either one- or two-sided stencil is + * enabled, dsa->stencil[0].enabled will be true. + */ if (dsa->depth.enabled || dsa->stencil[0].enabled) { const enum pipe_format zs_format = cell->framebuffer.zsbuf->format; boolean write_depth_stencil; - int fbZ_reg = spe_allocate_available_register(f); /* Z values */ - int fbS_reg = spe_allocate_available_register(f); /* Stencil values */ + /* We may or may not need to allocate a register for Z or stencil values */ + boolean fbS_reg_set = false, fbZ_reg_set = false; + unsigned int fbS_reg, fbZ_reg = 0; + + spe_comment(f, 0, "Loading Z/stencil tile"); /* fetch quad of depth/stencil values from tile at (x,y) */ /* Load: fbZS_reg = memory[depth_tile_reg + offset_reg] */ + /* XXX Not sure this is allowed if we've only got a 16-bit Z buffer... */ spe_lqx(f, fbZS_reg, depth_tile_reg, quad_offset_reg); - if (dsa->depth.enabled) { - /* Extract Z bits from fbZS_reg into fbZ_reg */ - if (zs_format == PIPE_FORMAT_S8Z24_UNORM || - zs_format == PIPE_FORMAT_X8Z24_UNORM) { - int mask_reg = spe_allocate_available_register(f); - spe_fsmbi(f, mask_reg, 0x7777); /* mask[0,1,2,3] = 0x00ffffff */ - spe_and(f, fbZ_reg, fbZS_reg, mask_reg); /* fbZ = fbZS & mask */ - spe_release_register(f, mask_reg); - /* OK, fbZ_reg has four 24-bit Z values now */ - } - else if (zs_format == PIPE_FORMAT_Z24S8_UNORM || - zs_format == PIPE_FORMAT_Z24X8_UNORM) { - spe_rotmi(f, fbZ_reg, fbZS_reg, -8); /* fbZ = fbZS >> 8 */ - /* OK, fbZ_reg has four 24-bit Z values now */ - } - else if (zs_format == PIPE_FORMAT_Z32_UNORM) { - spe_move(f, fbZ_reg, fbZS_reg); - /* OK, fbZ_reg has four 32-bit Z values now */ - } - else if (zs_format == PIPE_FORMAT_Z16_UNORM) { - spe_move(f, fbZ_reg, fbZS_reg); - /* OK, fbZ_reg has four 16-bit Z values now */ - } - else { - ASSERT(0); /* invalid format */ - } - - /* Convert fragZ values from float[4] to 16, 24 or 32-bit uint[4] */ - if (zs_format == PIPE_FORMAT_S8Z24_UNORM || - zs_format == PIPE_FORMAT_X8Z24_UNORM || - zs_format == PIPE_FORMAT_Z24S8_UNORM || - zs_format == PIPE_FORMAT_Z24X8_UNORM) { - /* scale/convert fragZ from float in [0,1] to uint in [0, ~0] */ - spe_cfltu(f, fragZ_reg, fragZ_reg, 32); - /* fragZ = fragZ >> 8 */ - spe_rotmi(f, fragZ_reg, fragZ_reg, -8); - } - else if (zs_format == PIPE_FORMAT_Z32_UNORM) { - /* scale/convert fragZ from float in [0,1] to uint in [0, ~0] */ - spe_cfltu(f, fragZ_reg, fragZ_reg, 32); - } - else if (zs_format == PIPE_FORMAT_Z16_UNORM) { - /* scale/convert fragZ from float in [0,1] to uint in [0, ~0] */ - spe_cfltu(f, fragZ_reg, fragZ_reg, 32); - /* fragZ = fragZ >> 16 */ - spe_rotmi(f, fragZ_reg, fragZ_reg, -16); - } - } - else { - /* no Z test, but set Z to zero so we don't OR-in garbage below */ - spe_load_uint(f, fbZ_reg, 0); /* XXX set to zero for now */ + /* From the Z/stencil buffer format, pull out the bits we need for + * Z and/or stencil. We'll also convert the incoming fragment Z + * value in fragZ_reg from a floating point value in [0.0..1.0] to + * an unsigned integer value with the appropriate resolution. + */ + switch(zs_format) { + + case PIPE_FORMAT_S8Z24_UNORM: /* fall through */ + case PIPE_FORMAT_X8Z24_UNORM: + if (dsa->depth.enabled) { + /* We need the Z part at least */ + setup_optional_register(f, &fbZ_reg_set, &fbZ_reg); + /* four 24-bit Z values in the low-order bits */ + spe_and_uint(f, fbZ_reg, fbZS_reg, 0x00ffffff); + + /* Incoming fragZ_reg value is a float in 0.0...1.0; convert + * to a 24-bit unsigned integer + */ + spe_cfltu(f, fragZ_reg, fragZ_reg, 32); + spe_rotmi(f, fragZ_reg, fragZ_reg, -8); + } + if (dsa->stencil[0].enabled) { + setup_optional_register(f, &fbS_reg_set, &fbS_reg); + /* four 8-bit Z values in the high-order bits */ + spe_rotmi(f, fbS_reg, fbZS_reg, -24); + } + break; + + case PIPE_FORMAT_Z24S8_UNORM: /* fall through */ + case PIPE_FORMAT_Z24X8_UNORM: + if (dsa->depth.enabled) { + setup_optional_register(f, &fbZ_reg_set, &fbZ_reg); + /* shift by 8 to get the upper 24-bit values */ + spe_rotmi(f, fbS_reg, fbZS_reg, -8); + + /* Incoming fragZ_reg value is a float in 0.0...1.0; convert + * to a 24-bit unsigned integer + */ + spe_cfltu(f, fragZ_reg, fragZ_reg, 32); + spe_rotmi(f, fragZ_reg, fragZ_reg, -8); + } + if (dsa->stencil[0].enabled) { + setup_optional_register(f, &fbS_reg_set, &fbS_reg); + /* 8-bit stencil in the low-order bits - mask them out */ + spe_and_uint(f, fbS_reg, fbZS_reg, 0x000000ff); + } + break; + + case PIPE_FORMAT_Z32_UNORM: + if (dsa->depth.enabled) { + setup_optional_register(f, &fbZ_reg_set, &fbZ_reg); + /* Copy over 4 32-bit values */ + spe_move(f, fbZ_reg, fbZS_reg); + + /* Incoming fragZ_reg value is a float in 0.0...1.0; convert + * to a 32-bit unsigned integer + */ + spe_cfltu(f, fragZ_reg, fragZ_reg, 32); + } + /* No stencil, so can't do anything there */ + break; + + case PIPE_FORMAT_Z16_UNORM: + if (dsa->depth.enabled) { + /* XXX Not sure this is correct, but it was here before, so we're + * going with it for now + */ + setup_optional_register(f, &fbZ_reg_set, &fbZ_reg); + /* Copy over 4 32-bit values */ + spe_move(f, fbZ_reg, fbZS_reg); + + /* Incoming fragZ_reg value is a float in 0.0...1.0; convert + * to a 16-bit unsigned integer + */ + spe_cfltu(f, fragZ_reg, fragZ_reg, 32); + spe_rotmi(f, fragZ_reg, fragZ_reg, -16); + } + /* No stencil */ + break; + + default: + ASSERT(0); /* invalid format */ } - + /* If stencil is enabled, use the stencil-specific code + * generator to generate both the stencil and depth (if needed) + * tests. Otherwise, if only depth is enabled, generate + * a quick depth test. The test generators themselves will + * report back whether the depth/stencil buffer has to be + * written back. + */ if (dsa->stencil[0].enabled) { - /* Extract Stencil bit sfrom fbZS_reg into fbS_reg */ - if (zs_format == PIPE_FORMAT_S8Z24_UNORM || - zs_format == PIPE_FORMAT_X8Z24_UNORM) { - /* XXX extract with a shift */ - ASSERT(0); - } - else if (zs_format == PIPE_FORMAT_Z24S8_UNORM || - zs_format == PIPE_FORMAT_Z24X8_UNORM) { - /* XXX extract with a mask */ - ASSERT(0); - } - } - else { - /* no stencil test, but set to zero so we don't OR-in garbage below */ - spe_load_uint(f, fbS_reg, 0); /* XXX set to zero for now */ - } + /* This will perform the stencil and depth tests, and update + * the mask_reg, fbZ_reg, and fbS_reg as required by the + * tests. + */ + ASSERT(fbS_reg_set); + ASSERT(fbZ_reg_set); + spe_comment(f, 0, "Perform stencil test"); - if (dsa->stencil[0].enabled) { - /* XXX this may involve depth testing too */ - // gen_stencil_test(dsa, f, ... ); - ASSERT(0); + write_depth_stencil = gen_stencil_depth_test(f, dsa, facing_reg, mask_reg, fragZ_reg, fbZ_reg, fbS_reg); } else if (dsa->depth.enabled) { int zmask_reg = spe_allocate_available_register(f); - gen_depth_test(dsa, f, mask_reg, fragZ_reg, fbZ_reg, zmask_reg); + spe_comment(f, 0, "Perform depth test"); + write_depth_stencil = gen_depth_test(f, dsa, mask_reg, fragZ_reg, fbZ_reg, zmask_reg); spe_release_register(f, zmask_reg); } - - /* do we need to write Z and/or Stencil back into framebuffer? */ - write_depth_stencil = (dsa->depth.writemask | - dsa->stencil[0].write_mask | - dsa->stencil[1].write_mask); + else { + write_depth_stencil = false; + } if (write_depth_stencil) { /* Merge latest Z and Stencil values into fbZS_reg. * fbZ_reg has four Z vals in bits [23..0] or bits [15..0]. * fbS_reg has four 8-bit Z values in bits [7..0]. */ + spe_comment(f, 0, "Storing depth/stencil values"); if (zs_format == PIPE_FORMAT_S8Z24_UNORM || zs_format == PIPE_FORMAT_X8Z24_UNORM) { - spe_shli(f, fbS_reg, fbS_reg, 24); /* fbS = fbS << 24 */ - spe_or(f, fbZS_reg, fbS_reg, fbZ_reg); /* fbZS = fbS | fbZ */ + if (fbS_reg_set) { + spe_shli(f, fbS_reg, fbS_reg, 24); /* fbS = fbS << 24 */ + spe_or(f, fbZS_reg, fbS_reg, fbZ_reg); /* fbZS = fbS | fbZ */ + } + else { + spe_move(f, fbZS_reg, fbZ_reg); + } } else if (zs_format == PIPE_FORMAT_Z24S8_UNORM || zs_format == PIPE_FORMAT_Z24X8_UNORM) { spe_shli(f, fbZ_reg, fbZ_reg, 8); /* fbZ = fbZ << 8 */ - spe_or(f, fbZS_reg, fbS_reg, fbZ_reg); /* fbZS = fbS | fbZ */ + if (fbS_reg_set) { + spe_or(f, fbZS_reg, fbS_reg, fbZ_reg); /* fbZS = fbS | fbZ */ + } } else if (zs_format == PIPE_FORMAT_Z32_UNORM) { spe_move(f, fbZS_reg, fbZ_reg); /* fbZS = fbZ */ @@ -1341,11 +2028,10 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) spe_stqx(f, fbZS_reg, depth_tile_reg, quad_offset_reg); } - spe_release_register(f, fbZ_reg); - spe_release_register(f, fbS_reg); + release_optional_register(f, &fbZ_reg_set, fbZ_reg); + release_optional_register(f, &fbS_reg_set, fbS_reg); } - /* Get framebuffer quad/colors. We'll need these for blending, * color masking, and to obey the quad/pixel mask. * Load: fbRGBA_reg = memory[color_tile + quad_offset] @@ -1354,8 +2040,8 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) */ spe_lqx(f, fbRGBA_reg, color_tile_reg, quad_offset_reg); - if (blend->blend_enable) { + spe_comment(f, 0, "Perform blending"); gen_blend(blend, blend_color, f, color_format, fragR_reg, fragG_reg, fragB_reg, fragA_reg, fbRGBA_reg); } @@ -1369,19 +2055,21 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) int rgba_reg = spe_allocate_available_register(f); /* Pack four float colors as four 32-bit int colors */ + spe_comment(f, 0, "Convert fragment colors to framebuffer colors"); gen_pack_colors(f, color_format, fragR_reg, fragG_reg, fragB_reg, fragA_reg, rgba_reg); if (blend->logicop_enable) { + spe_comment(f, 0, "Compute logic op"); gen_logicop(blend, f, rgba_reg, fbRGBA_reg); } if (blend->colormask != PIPE_MASK_RGBA) { + spe_comment(f, 0, "Compute color mask"); gen_colormask(f, blend->colormask, color_format, rgba_reg, fbRGBA_reg); } - /* Mix fragment colors with framebuffer colors using the quad/pixel mask: * if (mask[i]) * rgba[i] = rgba[i]; @@ -1393,6 +2081,7 @@ cell_gen_fragment_function(struct cell_context *cell, struct spe_function *f) /* Store updated quad in tile: * memory[color_tile + quad_offset] = rgba_reg; */ + spe_comment(f, 0, "Store framebuffer colors"); spe_stqx(f, rgba_reg, color_tile_reg, quad_offset_reg); spe_release_register(f, rgba_reg); -- cgit v1.2.3